1. Field
One embodiment of the present invention relates to an electronic apparatus having a wireless communication function, a computer system, and a communication control method.
2. Description of the Related Art
Recently, there have been developed various portable personal computers such as a laptop personal computer and a notebook personal computer. An extension unit called a docking station is also developed as an external apparatus which extends a function of the portable personal computer.
For example, Jpn. Pat. Appln. KOKAI Publication No. 2002-108521 discloses a system including an extension unit and a computer. In the system, a wired LAN controller is incorporated in the extension unit, and a wireless communication unit is incorporated in the computer. The computer is wirelessly connected to an access point by the wireless communication unit in an undocked state, and the computer is connected to a network through the wired LAN controller in the extension unit in a docked state.
Jpn. Pat. Appln. KOKAI Publication No. 2003-309749 discloses a camera system including a digital camera and an extension unit. In the camera system, an electric power is supplied from the extension unit to the digital camera through a cable, and data communication is conducted between the extension unit and the digital camera through the cable.
However, both in the systems disclosed in Jpn. Pat. Appln. KOKAI Publication Nos. 2002-108521 and 2003-309749, the electronic apparatus such as the computer and the camera and the extension unit thereof are connected in a wired manner. The wired connection becomes a factor for losing portability of the electronic apparatus such as the computer and the camera or a factor for restricting a point of use of the electronic apparatus.
When a wireless connection is established between the electronic apparatus and the extension unit thereof, the functional extension of the electronic apparatus can be realized without losing the portability of the electronic apparatus. However, usually there is a limitation to the number of usable frequency channels in a short-range wireless communication system in which devices are wirelessly connected. Therefore, in the particular point of use such as an office, when some devices already conduct the wireless communication with the short-range wireless communication system, the unused frequency channel runs out to hardly start the new wireless communication. Even if the unused frequency channel exists, sometimes wireless communication cannot normally be conducted depending on the surrounding radio wave environment.
Accordingly, even if the wireless communication units for the short-range wireless communication are mounted on the electronic apparatus and the extension unit, the wireless communication cannot always be conducted between the electronic apparatus and the extension unit.
Therefore, even in a situation in which the wireless communication cannot be conducted, there is a need for realizing a new function of being able to conduct the communication between the electronic apparatus and the external apparatus such as the extension unit.